Case of the month - October 2007 - discussion
Diagnosis - Post-irradiation angiosarcoma (high grade)
The thumbnail images alongside remind you of the main features in this biopsy - click on each thumbnail to return to the original images.
Features
The following features are seen:
- Spindle cell infiltration of the dermis with formation of clefts and solid nodules:
- High grade angiosarcomas usually show areas of more solid growth pattern.
- Moderate to severe cytological atypia with mitotic figures readily found:
- Better differentiated
tumours tend to be characterised by a preponderence of slit-like spaces and recognizable vascular
channels. In some of these cases it may be difficult to be certain that the lesion is truly sarcomatous
and not an atypical vascular proliferation related to previous radiotherapy. Caution is urged in these circumstances.
- Positive staining of tumour cells with CD31 & CD34 but only patchy staining with
Factor VIII:
- This is a recognised staining profile, particularly with more poorly
differentiated tumours where Factor VIII staining is absent or weak/patchy but CD31 and/or
CD34 are positive.
Additional information:
- The lesion was clinically typical of angiosarcoma and the interval between irradiation and its occurence appropriate (10 - 20 years)
Differential diagnosis:
- Spindle cell carcinoma - epithelial markers were negative
- Other sarcoma
